What is coeliac disease?In people with coeliac disease (pronounced ‘seel-ee-ak’ and spelt celiac in some countries) the immune system reacts abnormally to gluten (a protein found in wheat, rye, barley and oats), causing small bowel damage. The tiny, finger-like projections which line the bowel (villi) become inflamed and flattened. This is referred to as villous atrophy. Villous atrophy reduces the surface area of the bowel available for nutrient absorption, which can lead to various gastrointestinal and malabsorptive symptoms. Symptoms can also be caused by inflammation in other parts of the body.

Healthy Villi Damaged Villi

A number of serious health consequences can result if the condition is not diagnosed and treated properly.

Who gets coeliac disease?Coeliac disease affects people of all ages, both male and female.

You must be born with the genetic predisposition to develop coeliac disease. The most important genes associated with susceptibility to coeliac disease are HLA DQ2 and HLA DQ8. Either one or both of these genes are present in virtually every person with coeliac disease. While 30% of the population carry one or both of these genes, only 1 in 30 of these people (approximately) will get coeliac disease.

A first degree relative (parent, sibling, child) of someone with coeliac disease has about a 10% chance of also having the disease. If one identical twin has coeliac disease there is an approximate 70% chance that the other twin will also have coeliac disease (but may not necessarily be diagnosed at the same time).

Environmental factors play an important role in triggering coeliac disease in infancy, childhood or later in life.

How common is the condition?Coeliac disease affects on average approximately 1 in 70 Australians. However, approximately 80% currently remain undiagnosed. This means that approximately 330,000 Australians have coeliac disease but don’t yet know it.

More and more people are being diagnosed with coeliac disease. This is due to both better diagnosis rates and a true increase in the incidence of coeliac disease. Can coeliac disease be cured?People with coeliac disease remain sensitive to gluten throughout their life, so in this sense they are never cured. However, a strict gluten free diet does allow the condition to be managed effectively.

A strict, lifelong gluten free diet is currently the only recognised medical treatment for coeliac disease. By removing the cause of the disease, a gluten free diet allows the small bowel lining to heal and symptoms to resolve. As long as the gluten free diet is strictly adhered to, problems arising from coeliac disease should not return. Relapse occurs if gluten is reintroduced into the diet.

What are the long term risks of undiagnosed and untreated coeliac disease?The long term consequences of untreated coeliac disease are related to chronic systemic inflammation, poor nutrition and malabsorption of nutrients. For more information, see Associated Conditions.

Fortunately, timely diagnosis of coeliac disease and treatment with a gluten free diet can prevent or reverse many of the associated health conditions.

The Symptoms These vary considerably. Some people experience severe symptoms while others are asymptomatic (they have no obvious symptoms at all).

Symptoms can include one or more of the following:

• gastrointestinal symptoms e.g. diarrhoea, constipation, nausea, vomiting, flatulence, cramping, bloating, abdominal pain, steatorrhea

• fatigue, weakness and lethargy• iron deficiency anaemia and/or other vitamin and mineral

deficiencies• failure to thrive or delayed puberty in children• weight loss (although some people may gain weight)• bone and joint pains• recurrent mouth ulcers and/or swelling of mouth or tongue• altered mental alertness and irritability• skin rashes such as dermatitis herpetiformis• easy bruising of the skin

Why a medical diagnosis is importantAs coeliac disease is a serious medical condition with lifelong implications, a definitive diagnosis is essential. The gluten free diet is not a trivial undertaking and involves lifestyle changes and learning new skills such as reading and interpreting food labels. It should only be undertaken after the diagnosis of coeliac disease has been properly medically established.

If a gluten free diet has already been adopted prior to diagnosis, the tests used to diagnose coeliac disease are unreliable, and can be falsely negative.

By obtaining a proper diagnosis, you can be assured that your symptoms are caused by coeliac disease (and should therefore improve once the gluten free diet is established) and not by another more sinister condition.

How do I get diagnosed?The tests for coeliac disease are simple – just follow the steps below...

1. Keep eating gluten

Do not commence a gluten free diet prior to being tested for coeliac disease. If a gluten free diet has already been adopted, the tests used to diagnose coeliac disease are unreliable, and can be falsely negative.

If gluten has been removed from the diet, a normal diet must be resumed for at least six weeks prior to testing. During this ‘gluten challenge’, a minimum of four slices of wheat based bread (or equivalent) should be consumed each day (for adults) (two slices of wheat based bread each day for children). It is important the gluten challenge is carried out properly to ensure reliable test results.

How do I get diagnosed?2. Blood tests are used for screening

Blood tests (coeliac serology) are used to screen for coeliac disease. Coeliac serology measures antibody levels in the blood which are typically elevated in people with untreated coeliac disease, due to the body’s reaction to gluten.

These tests can be less reliable in children under the age of four years, as their antibody levels can fluctuate. It is suggested the antibody tests be performed on two occasions three months apart.

Importantly, a diagnosis of coeliac disease SHOULD NOT be made on the basis of a blood test alone. A positive blood test always needs to be followed by a small bowel biopsy to confirm the diagnosis.

How do I get diagnosed?3. A small bowel biopsy is essential to confirm diagnosis

A diagnosis of coeliac disease can only be made by demonstrating the typical small bowel changes of coeliac disease (villous atrophy). This involves a gastroscopy procedure in which several tiny samples (biopsies) of the small bowel are taken. A gastroscopy is a simple day procedure done under light anaesthetic sedation that takes about 10 minutes. In the majority of cases, the bowel damage present in those with untreated coeliac disease is not visible to the naked eye. The biopsies are examined under a microscope to confirm the presence of villous atrophy.

In some cases Genetic testing can be a helpful alternative to the small bowel biopsy.

The Gluten Free DietA strict gluten-free diet is the only medical treatment for coeliac disease. Removing gluten from the diet enables your gut to heal and your symptoms to improve.

What is gluten?

Gluten is a protein found in:

Wheat (including spelt) Rye Barley Oats (read our position statement on oats)

The Gluten Free DietWhat can I eat?There are four groups of food that are suitable for those on a gluten free diet:

1. Naturally gluten free foodsFor example: Fresh fruit and vegetables, fresh meats, eggs, nuts and legumes, milk, fats and oils and gluten free grains e.g. rice and corn.

2. Products labelled ‘gluten free’You can be confident that products labelled ‘gluten free’ contain no detectable gluten.

3. Products that use the ‘Crossed Grain Logo’Products displaying the Crossed Grain Logo are endorsed by Coeliac Australia and are tested to be suitable for people with coeliac disease. 4. Products that are gluten free by ingredientIf any ingredient in a product is derived from wheat, rye, barley or oats, then this must be declared on the ingredients panel. It is also important to avoid cross contamination by avoiding products with statements such as ‘may contain gluten’.

Choosing gluten free foodsCoeliac Australia produces an Ingredient List Booklet that lists over 800 ingredients and 300 additives used in Australian and New Zealand foods and indicates whether they are safe for inclusion in a gluten free diet. In order to follow a gluten free diet, it is essential to become ingredient aware and an expert label reader. As products and their ingredients change constantly, Coeliac Australia is not able to recommend brands of products. It is important to check the ingredients of the products you buy every time you shop. By becoming ingredient aware you are able to take control of your diet and increase your choice of suitable products.